HU208644B - Method and apparatus for removing sludge from settling pool or sedimentation basin - Google Patents

Abstract

Settled sludge is directed towards a collection sump. Typically, the sludge is allowed to settle on plates located near the bottom and washed off by liquid passed through the gaps between the plates, towards the sump. - The appts. comprises a basin with a bottom sloping towards a collection sump. Plates are fixed above the bottom with the outermost plates sealed against the basin inner surface. Liq. is supplied to the space under the plates, pref. by several washing connections.(Dwg. 0/1)

Description

FIELD OF THE INVENTION The present invention relates to a process and apparatus for the hydraulic removal of sludge selected from settling or settling sludges used in water and / or wastewater treatment.

It is known that in the above-mentioned purifiers and settlers, the sedimented material is deposited near the bottom - usually with a slight slope towards a sump. Removal of sludge from the artwork is, for the purposes of the prior art, mostly carried out by means of a mechanical excavator blade structure. A major disadvantage of known sludge removal devices is that the underwater dredger is frequently malfunctioning and therefore needs to be shut down for longer or shorter periods of time in the process. This problem is often addressed by installing backup equipment, which, in turn, requires significant additional costs.

Hungarian patent specification No. 181562 discloses a solution for circular planks in which a mud drive is provided with a central drive to eliminate underwater gears and bearings, thereby reducing the possibility of failure. However, there are also problems with this solution, namely, the large diameter special crane bearings driving the excavator structure are extremely expensive; the excavator blades located in the center of the clearing area mounted on a flocculator suction tube rotated by a gear unit; however, this makes the introduction of raw water uncertain and difficult. In fact, raw water must be introduced into this rotating suction pipe so that leaks do not cause false flows.

A hydraulic method for removing sludge from a settling basin is also known. This involves installing an annular tubular system in the basin to transfer the flushing water to the sludge and to wash it in the sludge collecting space. The water required for sludge removal is pressed into the annular tubing by means of a dedicated pump. In addition, the so-called. a flocculator pump was bypassed and replaced with an air intake, using a Mammuth pump. However, air mixing leads to flocculation of the flakes, thereby interfering with settling. A further disadvantage is that the manifold splashes the mud near the perforation towards the sump; untreated sludge may rot, which is not allowed for drinking water treatment structures.

US Patent No. 2920978 discloses an anaerobic wastewater treatment plant having a conical side wall interrupted by a circumferential slot. Through this gap, a water-slurry mixture may flow from the reaction space to the post-settling cassettes.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a less expensive, efficient and reliable solution for the removal of sludge from purifiers and settlers used in wastewater and drinking water treatment.

The present invention is based on the discovery that by settling the sludge on a surface formed by slab-like overlapping slabs, the sludge can be easily and effectively washed off with the water discharged through these slits. The invention is further based on the discovery that sludge removal can be carried out very economically by using the energy of raw water or wastewater to be treated, or the energy of water circulated by the flocculator to cause flocculation.

Based on the above findings, the object of the present invention has been solved by a method of directing sedimented sludge to a sludge collecting site, in particular to a sludge sump, by fluid flow, characterized in that the sludge is and settling the sedimented slurry with the liquid discharged through the gaps between these plates, preferably parallel to each other, towards the collection point, in particular the sludge. In a preferred embodiment of the process, the crude liquid to be sedimented in the slots or / and the liquid removed from the basin, optionally partially purified, is discharged.

The apparatus according to the invention is installed in a basin having a sludge collection site, preferably a bottom plate formed with a slope towards the sump. The object of this apparatus is that, relative to one another, panels are arranged spaced above the bottom plate, the outer edge of the plate furthest from the sludge collecting site being secured to the basin surface in a watertight or substantially watertight manner; and a washing line for feeding fluid, preferably multiple, into the space below the plates.

A preferred embodiment of this apparatus is characterized in that the outer edge of the disc furthest from the sludge collection site is folded down, has a channel with an opening facing the space below the disks, and functions as a water distribution element into which one or more washing lines. According to another preferred feature of the invention, the wash conduit (s) are connected to a portion of the vertical central tube of the basin containing a flotation pump or a feed conduit for the liquid to be cleaned (settled).

The invention will now be described in more detail with reference to the accompanying drawings, which show preferred embodiments of the apparatus. In the drawings, Figure 1 is a schematic vertical sectional view of a clarifier equipped with an apparatus according to the invention which is provided with a flocculator pump;

Figure 2 is a schematic vertical sectional view of a clarifier having an apparatus according to the invention which does not have a flocculator pump;

Figure 3 is a schematic vertical sectional view of a clarifier incorporating the apparatus of the present invention, which, although having a flocculator pump, is connected to the raw water supply pipe for the sludge removal water.

HU 208 644 Β

1, the inwardly sloping cone reinforced concrete sidewall (2) and the bottom plate of the basin (1) of the basin, which is formed in the direction of arrow (a), is indicated by the reference numeral (3). . From the sump (5) the sludge line (12) marked with a dotted line emerges. The basin (2) has a conical deflection wall (4) outwardly inclined, which is supported by sloping ribs (17) below. Within the baffle (4) there is a vertical central tube (7) extending along the vertical geometric axis of the object (X), the lower end of which is above and near the sump (5). The upper end of the central tube (7) has an opening (18) of variable cross-section. The upper edge of the central tube (7) is slightly above the water level (vj) of the basin (2), the water surface exiting this tube corresponding to arrow (b) is denoted by the reference letter (v ₂ ). For the introduction of the raw liquid to be settled, a conduit (13) is provided in the central pipe (7), and drainage troughs (14) are provided for discharging the purified water; Purified water is discharged from the system according to arrows (g). In the upper end region of the central tube (7) there is a flocculator pump (6) which is operatively connected to the gear (8). The treatment bridge over the basin (2) is designated by reference numeral (9). (The operation of the facility and the sedimentation mechanism are known per se, so no explanation is given here.)

In accordance with the present invention, in the form of a shutter-like arrangement spaced over the inner surface of the base plate 3, the plates (10) are fixed to the base plate (3), following a slope of the base plate (a) There are slots (15) between the portions of the plate and below, respectively, which are oriented from top to bottom. The plate (11) farthest from the assembly (5) is formed as a water distribution element which is connected to the bottom plate (3) and the curved transition wall portion (19) between the side wall (2) so that the outer edge of this water distribution element (11) is folded back to form a partially enclosed distribution channel (20) into which a plurality of wash lines (16) extend. The wash lines (16) are guided along the conical baffle (4) on the outside and extend from the upper end of the central tube (7) where the flocculator pump (6) is integrated.

The apparatus according to the invention operates in the purifier according to Fig. 1 so that the water raised by the flocculator pump (6) flows into the washing lines (16) according to arrows (d) and through them (arrows (e)) (11). water distributor element. From here, the water enters a narrow space under the plates (10) and, flowing through the slots (15) in accordance with the arrows (/), slurries the sludge deposited on the plates (10) into a sludge (5). The washing lines (16) extend radially in plan view, are spaced at equal intervals or angles and can be determined by hydraulic dimensioning or experimentally.

The longitudinal flow purifier of Figure 2 has a basin (21) having a reinforced concrete sidewalls (22) and a bottom (23) formed with a slope (a) towards the sump (25). From the sump (25), a sludge line (26) flows out. The supply line (27), which flows above the sump (25) into the pool (21) and into which a closure (27a) is inserted, serves to deliver the liquid to be cleaned to the pool (21). The trough (28) serves to collect the purified water.

In accordance with the present invention, as a result of the (known) settling operation, a slightly overlapping, slightly overlapping, plate (10), which is fixed to the bottom plate, is provided for removal of sludge settling on the bottom plate (23). ) slope (a) as indicated by an arrow and oriented towards the sump (25) therebetween. Again, the plate furthest from the assembly (25) is formed as a water distribution element (11) having an outer, folded-out rim sealed to the bottom plate and in its distribution channel (20) extending from the feed line (27). . In this example, the entry of the water to be purified into the pool is indicated by arrows (c), and the purified water leaves the system according to arrow (g). Removal of sedimented sludge is effected by feeding raw water (sewage or raw water) through the washing line (24) into a narrow space under the plates (10) and washing the jets of water (through the slots (15)) in the direction of the arrows (f). (a) the sedimented sludge, which collects in the sump (25) and is discharged through the sludge conduit (26) in the direction of an arrow. All or part of the raw water can be used for sludge washing.

The solution of FIG. 3 differs from that of FIG. 1 in that the sludge removal fluid is not supplied by the flocculator pump (6). In Fig. 3, the structural elements already described with reference to Fig. 1 are denoted by the reference numerals already used therein, and the reference letters are used as appropriate. In this exemplary embodiment, the liquid required to wash the sludge from the bottom plate (3) to the sump (5) through the slots (15) in accordance with the arrows (/) through the branch line (29) extending from the feed line (13a) , and is provided through disconnected wash lines (30) which extend into the distribution channel (20) and are radially spaced from the top, with the same spacing or angles. In this case, the washing liquid is the raw water itself (wastewater to be treated), as in the case of Figure 2.

An essential advantage of the present invention is that it is able to provide a uniform and complete (spotless) removal of sludge without a machine mechanism (excavator) containing an underwater moving component.

The invention is, of course, not limited to the exemplary embodiments of the apparatus as described above, but may be practiced in various ways within the scope of the claims.

Claims (5)

PATENT CLAIMS A method for removing sludge settled in a clarification or settling basin, wherein the sludge is directed to a collection site, in particular a sludge sump, by fluid flow, characterized in that the sludge is formed by sheets (10) spaced over the bottom of the pool, and dropping the sedimented slurry with liquid discharged through the gaps (15) between these plates, preferably parallel to each other, towards the collection point, in particular the sludge (5; 25). Method according to Claim 1, characterized in that the crude liquid to be sedimented in the gaps (15) or / and the liquid (optionally partially purified) taken from the basin (1) is discharged. Apparatus for removing sludge settled in a decontamination or settling basin comprising a bottom plate (3; 23) formed with a slope (a) towards a sump (5; 25), preferably a bottom plate (3); 23) at a distance spaced relative to each other are sheets (10) of a shutter-like arrangement, of which the outer edge of the plate furthest from the sludge collecting space is fixed to the basin surface in a watertight or substantially watertight manner; and a flow line (16; 24) for feeding fluid, preferably multiple, into the space below the disks (10). Apparatus according to Claim 3, characterized in that the outer edge of the disc furthest from the sludge collection site is folded down, comprises a channel (20) with an opening facing the space below the disks (10) and functions as a water distribution element (11). , into which one or more washing lines (16; 24) extend. Apparatus according to claim 3 or 4, characterized in that the washing lines (16; 24) have a volume of a vertical central tube (7) of the basin (7) containing a flotation pump (6) or a liquid to be cleaned (settled). are connected to an inlet supply line.